7 phrases the best public speakers never say

Want to deliver the perfect presentation? These seven mistakes could undermine your credibility and alienate your audience.

Most public speakers rightfully focus on integrating particularly impactful phrases into their presentations.

What they leave out of their speeches, however, could be just as important.

Even with the best intentions, these utterances can damage a speaker's credibility and ruin a potentially great presentation.

Here are seven things you'll never hear from a seasoned public speaker:

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1. "I'm sorry"

Unless you've actually made a grave mistake, never apologize for unnecessary reasons---it serves only to discredit you and undermine your authority.

If an audience member asks you to return to a previous slide for clarification or speak more loudly, you should happily oblige--but don't draw attention to your misstep.

A good speaker doesn't apologize for a minor or perceived mistake; doing so only calls attention to something that would otherwise have gone unnoticed.

2. "I'm tired"

Whether you were up all night fretting about your speech, out drinking, or jet-lagged, there's no reason to announce it (especially if you're hungover).

Not only does copping to your compromised state indicate that you're not giving the audience your best--it's also an unprofessional and invalid excuse.

Great public speakers push through and deliver a great speech regardless of extenuating circumstances. The show must go on!

3. "I'm nervous"

Experiencing anxiety before a public speaking engagement is perfectly normal, but using it as an excuse or framing it as a negative does you no good. Instead, trust in your (well-prepared) self and keep the butterflies under wraps.

If you can work on managing your anxiety and harness the jitters into excitement, you just might have a little fun along the way.

4. "I'll make this quick"

The audience has made the decision to invest their time in your presentation, so telling them you'll "make it fast" not only devalues their investment--it's most likely a promise you can't keep.

The best speakers have rehearsed their talks tirelessly, so they know exactly how long their presentation is going to take.

Always leave enough time at the end to take questions, but don't rush. Public speakers are meant to inform and inspire, not to deliver a speech as quickly as possible.

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5. "Weren't you listening?"

Even if you very clearly answered someone's question in an earlier slide, and they very clearly weren't paying attention, never scold an audience member.

Great lecturers are as gracious as they are informative, so remain patient and polite (no matter how irritated you may be on the inside).

6. "I'll come back to that"

If an unexpected question throws you off your rhythm, takeadvantage of the audience's curiosity and enthusiasm and go with the flow.

If you promise to get back to a question and never do, the audience member who posed the question may feel neglected.

Instead, answer directly, and if need be, skip ahead to the corresponding slide. Professionalism and adaptability elevate the best speakers from the rest of the pack.

7. "I'm not totally sure, but here goes..."

Of course, it's okay to not know everything.You are only human, after all--but don't offer a half-hearted or underdeveloped answer if you're not sure of the correct response.

In lieu of exposing your uncertainty, ask for the inquirer's contact information and offer to get back to them after you've conducted more research.

A good public speaker knows what they don't know, and is also committed enough to follow through with curious audience members.

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